Trees!

One thing, beyond the volcanoes that reminds you of the age is the size (and variety) of trees. It's like each tree has a character and have been growing uninterrupted. Two huge trees right as you exit Kona airport are a prime example.

Haven't seen so many well preserved Banyan trees, in one place! There is an actual Banyan Drive in Hilo that is lined with huge banyan trees - right next to the ocean - worth a visit.